Hi Lee. The blotch colors represent to temperature of the cloud top picked up by the infrared sounder on the satellite. Becasuse the temperature of the atmosphere decreases with elevation, higher clouds are colder; lower - warmer. High clouds as viewed in the image can be that wispy cirrus high-up on an otherwise clear day or they could be the tops of deep thunderstorms, like the reds and deep reds over the gulf of Mexico disturbance and Katia on this particular image enhancement. The hurricane center has recently raised their probability of tropical storm formation in the GOMEX to 60% in the next 48h; i'd say closer to 90% given the very warm waters of the Gulf this time of year (and other factors inclding lessening wind shear). Cheers, CJ